Fixing of anionic dyestuffs to cellulosic fibers with cationic polymeric fatty acid polyalkylene polyamines

ABSTRACT

Cellulosic fibers are dyed by treatment with an anionic dye such as Calcocid Blue 2G (a tri-phenyl methane dye, color Index 42090) and a polyamine derived from polymeric fat acids such as the polyamine obtained by hydrogenating, in the presence of ammonia, the reaction product of ammonia and tall oil fatty acids. Paper is prepared by adding such dye and polyamine to the aqueous fiber dispersion prior to the formation of sheets.

United States Patent James L. Keen New Brighton, Minn. 7 15,544

Mar. 25, 1968 Nov. 9, 1971 General Mills, Inc.

Inventor Appl. No. Filed Patented Assignee 17 Claims, No Drawings U.S.Cl 162/162, 8/7, 8/85, 8/100, 162/179, 162/182, 260/583 Int. Cl D21h3/80 Field of Search... 162/179, 182, 162, 183, 181; 8/7,85,100;260/5831 References Cited UNITED STATES PATENTS 12/1949 Neubert162/164 3,281,470 10/1966 Vertnik 260/5831 2,694,633 11/1954 Patilioch162/182 2,730,446 1/1956 Hutchins 162/162 3,248,280 4/1966 Hyland 162/ 164 OTHER REFERENCES Casey, Pulp and Paper, V01. 11, 2 nd edition, pp.745- 747. Dyeing and Chemical Technology of Textile Fibers PrimaryExaminerS. Leon Bashore Assistant Examiner-Richard H. AndersonAttorneys-Anthony A. Juettner, William C. Babcock and Gene 0. EnocksonFIXING OF ANIONIC DYESTUFFS TO CELLULOSIC FIBERS WITH CATIONIC POLYMERICFATTY ACID POLYALKYLENE POLYAMINES The present invention relates to aprocess of dyeing cellulosic fibers and to the resulting product. In onespecific aspect, it particularly relates to the production of coloredpaper from cellulosic fibers wherein an anionic dye is used incombination with a polyamine derived from polymeric fat acids.

Perhaps the most used procedure for preparing colored paper is to add adye to the paper while it is still in the fibrous statei.e. prior tobeing formed on the machine. Such procedure is commonly referred to asbeater dyeing. The open top and vigorous mixing action of the beatermakes it an excellent place to add the dyes. However, the term beaterdyeing" is taken to include also dyeing in Hydropulpers, Dynopulpers,.lordans mixing chests, mixing tanks, fan pumps, head boxes and the likewhere similar mixing conditions exist.

The main classes of dyes used in the production of colored papers usingbeater dyeing are the acid, direct and basic dyes. The first twoclasses, namely the acid and direct dyes, are anionic in nature and aregenerally sodium salts of color acids. They are water soluble and areavailable in practically all shades of the rainbow. The acid dyes havelittle, if any, affinity for cellulose. Accordingly, they have mostcommonly been employed where the furnish also contains alum or both alumand rosin. l have now discovered that the retention of anionic dyes bycellulosic fibers can be improved if the fibers are treated with acombination of the anionic dye and a polyamine derived from a polymericfat acid. My process has particular application to the dyeing ofcellulosic fibers with acid dyes. However, it is also of value whenother anionic dyes such as the direct dyes are to be used. While theselatter materials have affinity for cellulosic fibers, the dyeingintensity can be increased with the use of polymeric fat acid basedpolyamines and the amount of the direct dyes needed to produce a certaincolor may be reduced. it is theorized that the polyamines employed arein some way held by the fibers and yet are capable of complexing orreacting with the anionic dyes to also hold same to an increased degreeto the fibers. The process is especially valuable in dyeing thecellulosic fibers prior to their formation into sheets although it isalso useful in dyeing already formed sheets of paper as well as fabricsand the like derived from cellulosic fibers such as cotton.

As indicated, the anionic dye and polymeric fat acid based polyamine arepreferably added to dilute dispersions of the cellulosic fibers prior tothe formation of sheets from such dispersions. Preferably, the additionis made to the beater or refiner or to the already beaten or refinedfiber. In the latter case, the dye and polyamine are thoroughly mixedwith the beaten or refined fibers. Any of the wide variety ofcommercially available beaters and/or refiners can be used. Thecellulosic fibers can be any of those used in papermaking, such as thosecommonly referred to as sulfite, soda, sulfate and ground wood stock, orfibers derived from rag, cotton, bast, flax and stem fibers such asstraw, or from repulped broke. The fibers may be bleached or unbleached.The concentration of the fibers in the aqueous dispersion is generallyless than about 4.0 percent by weight and preferably in the range of 0.5to 3.0 percent by weight.

The polymeric fat acid based polyamines useful in the present inventionare those having at least one polymeric fat acid radical and at leasttwo primary amine groups. The preferred amines are those having thefollowing formulae:

(I) R-EOHgNHn] where n is an integer of 2 to about 4, m is an integer of3 or 4, p is an integer of l or 2, x is an integer of 2 to about 40 orhigher, R is the polyvalent hydrocarbon radical of a polymeric fat acidand D is the divalent hydrocarbon radical of dimeric fat acid.Especially preferred compounds of the first two formulae are thosewherein n is 2. Such amines have the followk m ylaafl..-

(IIa) H N-(H mCm I IOH DCH,II CmHgm)NH,

m WWW..-

where m and D are as above defined.

As indicated all of such polyamines are derived from polymeric fatacids. Such polymerized fat acids are prepared by polymerizingethylenically unsaturated monobasic carboxylic acids having 16 to 22carbon atoms or the lower alkyl esters thereof. The preferred aliphaticacids are the mono and polyolefinically unsaturated 18 carbon atomacids. Representative octadecenoic acids are 4-octadecenoic,S-Octadecenoic, 6-octadecenoic (petroselinic), 7-octadecenoic,8-octadecenoic, cis-9octadecenoic (oleic), trans-9-octadecenoic(elaidic), ll-octadecenoic (vaccenic), l2-octadecenoic and the like.Representative octadecadienoic acids are 9,12-octadecadienoic(linoleic), 9,1 l-octadecadienoic, l0,l2-octadecadienoic,12,15-octadecadienoic and the like. Representative octadecadienoic acidsare 9,l2,15-octadecatrienoic (linolenic), 6,9,12-octadecatrienoic, 9,1 ll 3-octadecatrienoic (eleostearic), 10, l 2, l 4-octadecatrienoic(pseudoeleostearic) and the like. A representative 18 carbon atom acidhaving more than three double bonds is moroctic acid which is indicatedto be 4,8,12,l5-octadecatetraienoic acid. Representative of the lesspreferred (not as readily available commercially) acids are:7-hexadecenoic, 9-hexadecenoic (palmitoleic), 9-eicosenoic (gadoleic), 1l-eicosenoic, 6,10, l4hexadecatrienoic (hiragonic),4,8,12,16-eicosatetraenoic, 4,8,12,15,18-eicosapentanoic (timnodonic),l3- docosenoic (erucic), l l-docosenoic (cetoleic), and the like.

The ethylenically unsaturated acids can be polymerized using knowncatalytic or noncatalytic polymerization techniques. With the use ofheat alone, the mono-olefinic acids (or the esters thereof) arepolymerized at a very slow rate while the polyolefinic acids (or theesters thereof) are polymerized at a reasonable rate. If the doublebonds of the polyolefinic acids are in conjugated positions, thepolymerization is more rapid than when they are in the nonconjugatedpositions. Clay catalysts are commonly used to accelerate thedimerization of the unsaturated acids. Lower temperatures are generallyused when a catalyst is employed.

The polymerization of the described ethylenically unsaturated acidsyields relatively complex products which usually contain a predominantportion of dimerized acids, at smaller quantity of trimerized and higherpolymeric acids and some residual monomers. The dimerized acids having32 to 44 carbon atoms can be obtained in reasonably high purity from thepolymerization products by vacuum distillation at low pressures, solventextraction or other known separation procedures. The polymerizationproduct varies somewhat depending on the starting fat acid or mixturethereof and the polymerization technique employedi.e. thermal,catalytic, particular catalyst, conditions of pressure, temperature,etc. Likewise, the nature of the dimerized acids separated from thepolymerization product also depends somewhat on these factors althoughsuch acids are functionally similar.

Analysis of dimerized acids prepared from linoleic acid rich startingmaterials using heat alone or heat plus a catalyst, such as an acid oralkaline clay, shows that the product contains structurally similaracids having monocyclic tetra-substituted ring structures as well asacids with two and three rings, such additional rings generally beingfused to the six carbon atom ring. The clay catalyzed dimerized acidshave been shown to contain some aromatic rings according to ultravioletand infrared spectroscopy. These aromatic rings are believed to beformed by hydrogen transfer (by catalytic action of clay) from asubstituted cyclohexene ring to form a substituted benzene ring.Polymerization of pure oleic acid using a clay catalyst has been shownto yield a mixture of dimerized fat acids of which approximately -30percent by weight have a one ring cyclic structure with the remainderbeing noncyclic. However, when mixtures of oleic and linoleic acids(such as from tall oil) are polymerized, the resulting dimerized fatacid contains little if any dimer having a noncyclic structure.

It is apparent from the above and other published analyses that thepolymerization of the ethylenically unsaturated acids yields complexproducts. The dimer fraction thereof, generally consisting of a mixtureof acids, can be assigned the formula:

HOOC-D COOH where D is a divalent hydrocarbon group containing to 42carbon atoms. It is also apparent that said divalent hydrocarbon groupis complex since a mixture of acids normally results from thepolymerization and subsequent fractionation. These acids have structuraland functional similarities. Thus such mixture of acids contains asignificant proportion of acids having a six carbon atom ring (about 25percent or more even when the starting fat acid is a mono-olefinicallyunsaturated acid such as oleic). The remaining carbon atoms in thedivalent hydrocarbon group of such ring containing acids are thendivided between divalent and monovalent radicals which may be saturatedor ethylenically unsaturated. Such radicals may form one or moreadditional cyclic structures which are generally fused to the first sixmembered ring. Many of such dimeric acids may be considered as having atheoretical idealized, general fonnula as follows:

R R CO OH R R"--COOH where R and R" are divalent hydrocarbon radicals,R' and R"" are monovalent hydrocarbon radicals and the sum of the carbonatoms in RR"" is 24 -36. The ring may be saturated or it may contain oneto three double bonds depending on the specific starting material,polymerization conditions and subsequent treatment includinghydrogenation. It is also understood that the R-R"" radicals may formone or more additional cyclic structures which are generally fused tothe first ring.

As a practical matter, the dimeric fat acids are preferably prepared bythe polymerization of mixtures of acids (or the simple aliphatic alcoholesters-Le. the methyl esters) derived from the naturally occurringdrying and semidrying oils or similar materials. Suitable drying orsemidrying oils include soybean, linseed, tung, perilla, oiticia,cottonseed, corn, sunflower, dehydrated castor oil and the like. Also,the most readily available acid is linoleic or mixtures of the same witholeic, linolenic and the like. Thus, it is preferred to use as thestarting materials, mixtures which are rich in linoleic acid. Anespecially preferred material is the mixture of acids obtained from talloil which mixture is composed of approximately 40-45 percent linoleicand -55 percent oleic. It is also preferred to carry out thepolymerization in the presence of a clay. Partial analysis of arelatively pure dimer fraction (98.5 percent dimer) obtained from theproduct prepared by polymerizing the tall oil fatty acids in thepresence of 10 percent by weight of an alkaline montmorillonite clay ata temperature of 230 C. and a pressure of 140 p.s.i. for 5 hours showedthat it was a mixture of C acids. the major proportion thereof beingmonocyclic of the above general formula with a substantial amount of theacids having a ring containing three double bonds (aromatic) andsaturated side chains. Such mixture of acids was used in the preparationof the dinitrile and thence the various polyamines used in the examplesto follow. It is also to be understood that the correspondinghydrogenated dimeric fat acids are useful in preparing the dinitrilesand ultimately the polyamines employed in the present invention.

The polymerized fat acids are converted to the correspondingpolynitriles by reaction with ammonia under nitrile forming conditions.The details of this reaction are set forth in Chapter 2 of Fatty Acidsand Their Derivatives" by A. W. Ralston, John Wiley & Sons, lnc., NewYork 1948 The polyamines of the formulae (1.) and (1a.) above are thenprepared by hydrogenating the polynitriles in the presence of ammonia.Polyamines of this type are commercially available materials. Theirpreparation is further described in McCaleb et a1. Pat. No. 3,010,782which disclosure is incorporated herein by reference.

Polyamines of the formulae (11.) and (11a.) are also commerciallyavailable. Such polyamines are prepared by reacting the compounds offormulae (1.) and (1a.) with an unsaturated nitrile such asacrylonitrile, crotononitrile, and methacrylonitrile and thencatalytically reducing the resulting polynitrile. The preparation ofthese compounds are also further described in the above-identifiedMcCaleb et al. patent.

The polyamines of the formula (11].) are prepared by the condensationpolymerization of the dinitriles under secondary-amine-formingconditions. Typical reaction conditions utilize hydrogen pressures inthe range of 25 to 1000 p.s.i.g. at temperatures in the range of 200 to290 C. The preparative reaction is illustrated by the followingequation:

The ammonia byproduct is swept from the reaction mixture with hydrogengas. Various of these polyamines are also commercially available andtheir preparation is further described in Vertnik Pat. No. 3,217,028which disclosure is incorporated herein by reference.

The polyamines derived from the polymeric fat acids are used in anamount sufficient to increase the retention of the anionic dyes on thefibers. Preferably, the polyamines are used in an amount of about 0.05to 1.0 percent by weight based on the dry weight of the fibers.

Any of a wide variety of anionic dyes can be used in the presentinvention. Typical of such dyes are the following acid dyes: Nigrosine02P, Nigrosine OPX Dustless, Nigrosine 1, Acid Blue R, Acid Blue B, AcidBlue 2R, Acid Blue 38, Quinizol Blue BP, Bond Blue B Conc., Acid Green26 Conc. Dustless, Acid Orange Y Dustless, Acid Green Extra Conc., AcidOrange RR Dustless, Azo Scarlet Y Extra Conc., Crocein Scarlet MOO Conc.Dustless, Crocein Scarlet MOON, Serisine B, Fast Red Conc., AcidCarminette, Fast Acid Carminette SC, Metanil Yellow MXXX Conc. Dustless,Acid Violet 4BNS Dustless, Acid Violet 6B Conc., Chinoline Yellow WConc. and the like. These and other acid and direct dyes are disclosedin Dyestuff Data for Paper Makers," American cyanamid Company, 1952, pp.17-21 and 25-30 and in University of Maine Lectures on Pulp and PaperManufacture, 1950, pp. 241-245, the disclosures of which areincorporated herein by reference.

The amount of dye added to the cellulosic fiber is not critical and, ofcourse, depends on the strength of the dye and paper color desired.Preferably the dye is used in an amount of about 0.05 to 1.0 percent byweight based on the dry weight of the fibers.

The anionic dye is preferably added to the fiber in the form of a diluteaqueous solution or dispersion. Likewise, the polyamine is alsopreferably added in the form of a dilute aqueous solution or dispersion.Solubilization of the polyamine can be effected by at least partiallyneutralizing the same with a water soluble organic or inorganic acidsuch as acetic acid and mineral acids including hydrochloric, sulfuricand the like. The use of the dilute solutions or dispersions of dye andpolyamine results in a more even distribution thereof on the fibers. Itis also preferred that the said solutions or dispersions contain lessthan about 10 percent by weight of the polyamine and/or dye. In manyinstances, it is preferred that the polyamine is first added to thefibers followed by addition of the anionic dye. Where the materials areadded to already formed sheets or fabrics derived from cellulosicfibers, the polyamine solution or dispersion is also first preferablyapplied. ln papermaking, such addition can take place at the calendar.But generally, any method of dipping, spraying, etc. of the sheets orfabrics can be employed.

In the preferred procedure wherein the polyamine derived from polymericfat acids and the anionic dye are thoroughly mixed with an aqueous pulpor fiber dispersion, sheets can then be prepared using conventionaltechniques. In this respect, the relatively uniform dispersion of thepulp fibers containing the anionic dye and the polyamine is filteredthrough a screen which leaves a wet sheet on the screen. This sheet canthen be dried and otherwise processed to make paper which can be usedfor a variety of purposes including use as a nonwoven fabric. Any of thecommercially available forming machines can be used including theFourdrinier and cylinder machines. The wet sheets are preferably driedat temperatures of 200 F. to 250 F. to a moisture content of less thanabout percent. Any conventional drying technique can be used such assteam heated dryers.

It is also to be understood that conventional additives such as fillersand the like can be added. Representative fillers are talc, CaCO silica,TiO and so forth.

The following examples further illustrate and describe the process andproducts of the present invention and are not to be considered aslimiting. Unless otherwise indicated all parts and %s are by weight.

EXAMPLE 1 One liter samples of an aqueous dispersion of moderatelyrefined, bleached Kraft pulp at 0.8 percent solids at the pH of localtap water (about 7.9) were first prepared. To one sample was added cc.of a 0.2 percent aqueous solution of the acid dye Calcocid Blue 2G (atri-phenyl methane dye, Color Index 42090). To a second sample was added15 cc. of the dye solution and 4 cc. of a 1 percent aqueous solution ofa diamine (1 cc. diamine/lOO cc. water containing 0.2 cc. acetic acid)of the formula la. above derived as indicated from the mixture of Cacids prepared by polymerizing tall oil fatty acids. The dispersionswere thoroughly mixed and then single handsheets were made from suchpulp samples on a Nobel and Wood Handsheet machine. The wet sheets weredried on a rotary dryer at between 200 to 250 F. until they containedless than about 10 percent moisture. The sheets obtained from thedispersion containing the diamine were of a pretty pastel blue colorwhereas the sheets obtained from the dispersion containing only the dyewere not dyed to any noticeable extent being creamy white.

EXAMPLE ll Handsheets were prepared as in example 1 except that thediamine was replaced by a polyamine of the formula lla. above wherein mis 3 and D is the same as in the diamine of example I. The resultinghandsheets had a relatively deep blue color indicating that even more ofthe dye was retained than with the diamine as used in example i.

EXAMPLE lll Handsheets were prepared as in example I except that thediamine was replaced by a polyamine of the formula III above wherein xis an average of about 6 and D is the same as in the diamine of examplel. The resulting handsheets were of substantially the same pretty pastelblue color as those prepared from the diamine containing dispersion ofexample 1.

The embodiments of the invention in which an exclusive property orprivilege is claimed as defined as follows:

1. The process of dyeing cellulosic fibers which comprises treating suchfibers with l an aqueous solution of an anionic dye and (2) a polyaminehaving at least two primary amine groups and at least one polyvalenthydrocarbon group of polymerized fat acids derived from ethylenicallyunsaturated aliphatic monobasic carboxylic acids of 16 to 22 carbonatoms, said polyamine being used in an amount sufficient to increase theretention of the anionic dye by the fibers.

2. The process of claim 1 where in the polyamine is selected from thoseof the following formulae:

where n is an integer of 2 to about 4, m is an integer of 3 or 4, p isan integer of l or 2, x is an integer of at least 2, R is the polyvalenthydrocarbon radical of polymerized fat acids and D is the divalenthydrocarbon radical of dimerized fat acids, said polymerized anddimerized fat acids being derived from ethylenically unsaturatedaliphatic monobasic carboxylic acids of 16 to 22 carbon atoms.

3. The process of claim 1 wherein the polyamine has the formula: l-lN-Cl'l -D-cl-l -Nl-l where D is the divalent hydrocarbon radical ofdimerized fat acids derived from ethylenically unsaturated aliphaticmonobasic carboxylic acids of 16 to 22 carbon atoms.

4. The process of claim 1 wherein the polyamine has the formula:

HgN( Him C m I TCHgDC H;I l' C mH;m)N H;

where m is an integer of 3 or 4 and D is the divalent hydrocarbonradical of dimerized fat acids derived from ethylenically unsaturatedaliphatic monobasic carboxylic acids of 16 to 22 carbon atoms.

5. The process of claim 1 wherein the ethylenically unsaturatedaliphatic monobasic carboxylic acids contain 18 carbon atoms.

6. The process of claim 5 wherein the 18 carbon atom acids comprise amixture rich in linoleic acid.

7. The process of claim 1 wherein the polyamine is added to the fibersas an aqueous solution.

8. The process of claim 1 wherein the polyamine is ,used in an amount ofabout 0.05 to 1.0 percent by weight based on the dry weight of thefibers.

9. The process of claim 8 wherein the anionic dye is an acid dye.

10. The process of claim 9 wherein the polyamine has the fonnula:

where D is the divalent hydrocarbon radical derived from a mixture of 18carbon atom ethylenically unsaturated aliphatic monobasic carboxylicacids rich in linoleic acid.

1 1. In the process of preparing colored paper from an aqueousdispersion of cellulosic fibers and an anionic dye, the improvementcomprising adding a polyamine having at least two primary amine groupsand at least one polyvalent hydrocarbon group of polymerized fat acidsderived from ethylenically unsaturated aliphatic monobasic carboxylicacids of lo to 22 carbon atoms to the dispersion before forming thedispersion into sheets, said polyamine being used in an amountsufficient to increase the retention of the anionic dye by thecellulosic fibers.

12. The process of claim 11 wherein both the anionic dye and thepolyamine are added to the fiber dispersion as dilute aqueousdispersions or solutions.

13. The process of claim 12 wherein the polyamine is selected from thoseof the following formulae:

where n is an integer of 2 to about 4, m is an integer of 3 or 4, p isan integer of 1 or 2, x is an integer of at least 2, R is the polyvalenthydrocarbon radical of polymerized fat acids and D is the divalenthydrocarbon radical of dimerized fat acids, said 15. The process ofclaim 14 wherein D is the divalent hydrocarbon radical derived from amixture of 18 carbon atom ethylenically unsaturated aliphatic monobasiccarboxylic acids rich in linoleic acid.

16. The product prepared by the process of claim 1.

17. The paper product prepared by the process of claim lll.

2. The process of claim 1 where in the polyamine is selected from thoseof the following formulae:
 3. The process of claim 1 wherein thepolyamine has the formula: H2N-CH2-D-CH2-NH2 where D is the divalenthydrocarbon radical of dimerized fat acids derived from ethylenicallyunsaturated aliphatic monobasic carboxylic acids of 16 to 22 carbonatoms.
 4. The process of claim 1 wherein the polyamine has the formula:where m is an integer of 3 or 4 and D is the divalent hydrocarbonradical of dimerized fat acids derived from ethylenically unsaturatedaliphatic monobasic carboxylic acids of 16 to 22 carbon atoms.
 5. Theprocess of claim 1 wherein the ethylenically unsaturated aliphaticmonobasic carboxylic acids contain 18 carbon atoms.
 6. The process ofclaim 5 wherein the 18 carbon atom acids comprise a mixture rich inlinoleic acid.
 7. The process of claim 1 wherein the polyamine is addedto the fibers as an aqueous solution.
 8. The process of claim 1 whereinthe polyamine is used in an amount of about 0.05 to 1.0 percent byweight based on the dry weight of the fibers.
 9. The process of claim 8wherein the anionic dye is an acid dye.
 10. The process of claim 9wherein the polyamine has the formula: where D Is the divalenthydrocarbon radical derived from a mixture of 18 carbon atomethylenically unsaturated aliphatic monobasic carboxylic acids rich inlinoleic acid.
 11. In the process of preparing colored paper from anaqueous dispersion of cellulosic fibers and an anionic dye, theimprovement comprising adding a polyamine having at least two primaryamine groups and at least one polyvalent hydrocarbon group ofpolymerized fat acids derived from ethylenically unsaturated aliphaticmonobasic carboxylic acids of 16 to 22 carbon atoms to the dispersionbefore forming the dispersion into sheets, said polyamine being used inan amount sufficient to increase the retention of the anionic dye by thecellulosic fibers.
 12. The process of claim 11 wherein both the anionicdye and the polyamine are added to the fiber dispersion as diluteaqueous dispersions or solutions.
 13. The process of claim 12 whereinthe polyamine is selected from those of the following formulae:
 14. Theprocess of claim 13 wherein the anionic dye is an acid dye and thepolyamine is used in an amount of about 0.05 to 1.0 percent by weightbased on the dry weight of the fibers and has the formula
 15. Theprocess of claim 14 wherein D is the divalent hydrocarbon radicalderived from a mixture of 18 carbon atom ethylenically unsaturatedaliphatic monobasic carboxylic acids rich in linoleic acid.
 16. Theproduct prepared by the process of claim
 1. 17. The paper productprepared by the process of claim 11.